Information and redundancy in the legend of Theseus

This paper considers an instance of non‐verbal graphic communication from the legend of Theseus, in terms of information theory. The efficient cause of a failure in communication is regarded as a selection error and the formal cause as the absence of redundancy from the signals (a binary contrast between a black and a white sail) for transmission. Two considerations are then introduced. First, why should such a system of signalling have been succeeded by a graphic communication system, in alphabetic written language, so strongly marked by its redundancy? Second, why has information theory been so successful in describing systems for signal transmission but far less productive for modelling human‐to‐human communication, at the level of meaning or of the effects of messages on recipients? The legend is read historically, adopting specific insights, a method of interpretation, and a historical schema from Vico. The binary code used for the signal transmission is located as a rare but significant transitional form, mediating between heroic emblems and written language. For alphabetic written language, a link to the sounds of oral utterance replaces the connection to the mental states of the human information source and destination. It is also suggested that redundancy was deliberately introduced to counteract the effects of selection errors and noise. With regard to information theory, it is suggested that conformity with necessary conditions for signal transmission, which may include the introduction of redundancy, cannot be expected to yield insights into communication, at the level of meaning or the effects of messages.